Reserve dyeing on vegetable fibers



45 the desired esterification. This process af-.

Patented Aug. 7, 1 928 UNITED STATES 1,679,478 PATENT OFFICE.

HANS LEEMANN, OF BOTTMINGERMUHLE-BINNINGEN, NEAR BASEL, AND GIOVANNI TAGLIANI, or BASEL, SWITZERLAND,

ASSIGNORS, BY MESNE ASSIGNMENTS, TO

MUNITEX CORPORATION, OF LOIJI, NEW JERSEY, A CORPORATION 01 NEW JERSEY.

RESERVE DYEING ON VEGETABLE FIBERS.

Nobrawing. Original application filed April 27, 1925, Serial No. 26,289, and in Germany May 7, 1924. Divided and this application filed May 20, 1926. Serial No. 110,538.

This application is divisional of application Ser. No. 26,289.

The hitherto known reserve processes consist of mechanical or chemical operations.

To the first type belongs the binding and the covering of the vegetable fibers (yarns and fabrics) by substances insoluble in water so that the dyestuffs employed can only soak in and be fixed on the unbound or uncovered parts of the fabric. To the second class helongs the application of certain agents, preferably of salts, which react chemically during the dyeing or during the development of the dyes. All these processes depend, however, on certain conditions. If the reserve agents employed are removed during the dyeing process or during the development of the dyes, or if they do not resist these operations untilthe end of the dyeing, then the desired reserve effect does not occur and the fabric is dyed uniformly throughout as iflthe reserving agents had not been used at al It is known from German specification No. 346,883 and others that it is possible to render vegetable fibers (yarns, loose material, fabrics) completely immune against substantive dyestufi's by treating them after alkalinization with solutions of aromatic carboxylic acid chlorides or aromatic sulpho acid chlorides. Both the alkalinization and the action of the aromatic acid or sulpho acid chlorides are so efi'ected that the whole of the vegetable fibers is brought into the solutions of the respective agents.

It has now been shown in' a surprising manner that this esterification can also be used for the topical alteration of the vegetable fibers, in view of the production of reserve efi'ects, for example in a suitable printing process. It was not at all to be foreseen from the more active treatment in solution that the short superficial and sparing local treatment, as it takes place for example in the printing process, would sufiice to produce fords permanently reservingspatterns with unexpected dyeing properties, which remain fast even after hot washing operations, after hot neutral, acid or alkaline dye baths.

The production of such reserve effects is now utilized in the process for reserve. dye

ing on vegetable fibers forming the subject of the present invention. This process consists in first treating topically the vegetable fibers by a local printing with a suitable alkalizing agent, such as for example as concentrated alkaline solution, with or without thickening agent, with or without the addition of alcohol, with or without an alcoholic solution of an alkali alcoholate, then in applying thereon in dry or moist condition, an esterifying aromatic acid chloride, such as an aromatic carboxylic acid chloride, or an aromatic sulpho acid chloride, in pure or dissolved condition, and finally after the resulting esterification, in thoroughly washing the vegetable fibers being thus locally altered at the places of the aforesaid print to constitute what is commonly terme as reserve efiects. Thereupon the thus topically altered fibers are dyed first with an acid dyestufi and then with a substantive dyestuff. The acid dyestuff is fixed by the esterified parts, while the substantive one is fixed by the other parts of the fibers.

As dyestuffs, there may be used the usual coloring matters which are suitable for carrying out the improved process. The fibers may be in form of loose material, yarns or fabrics.

What we claim is:

1. A process for reserve dyeing on vegetable fibers, which consists in treating.

topically the vegetable fibers by a local printing with an alkalizing agent, thereupon applying an esterifying aromatic acid chloride to produce a topical alteration of the locally printed fiber, thus constituting reserve ef fects, then washing after the esterification, and thereupon dyeing the thus topically altered fibers first with an acid dyestufi an then with a substantive dyestufi.

2. A process for the reserve dyeing on vegetable fibers, which consists in treatin topically the vegetable fibers by a loos. printing with an alkalizing agent, thereupon applying an esterifying aromatic sulpho acid chloride to produce a' topical alteration of the locally printed fiber, thus constituting reserve effects, then washing after the esterification, and thereupon dyeing the thus topically altered fibers first with an- 3. A process for reserve dyeing on vegealkalizing agent, esterifying said treated areas with an aromatic sulpho acid chloride whereby reserve effects are produced, washing said fibers and dyeing said treated areas first with an acid dyestuif and then with a substantive dyestuif.

In witness whereof we have hereunto signed our names this 10th day of May 1926.

HANS LEEMANN. GIOVANNI TAGLIANI. 

